In addition to the cost of building the Website itself, there are at least 3 other major things to consider with ecommerce:
A Merchant Account with your Bank

Before online commerce is even possible for your business, you need a Merchant Account with your Bank. There is usually a non-refundable Application Fee. The Merchant account then attracts standard Monthly Maintenance fees of around $10 Per Month.
A Secure Server Certificate for the Website

Finding a reliable website creator is important. Likewise, finding the best and most reliable online casino slots is just as important.

A Secure Server Certificate is a requirement for Ecommerce. You can use what is known as a “shared certificate”. However, this will show your Customer the name of your ISP / Hosting Provider on their Credit Card Statement, and some people get confused if it does not show your actual Web Site name when they receive their Statement. This is where a lot of chargebacks occur, since Customers do not actually realise they have been charged legitimately.

Standard Merchant Account Bank Fees
These are usually based on Volume of Sales. and of course, standard Account Maintenance Fees. The average rate from the Bank of New Zealand is 4.5% (minimum) for example for each batch of Transactions.